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Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene
Published on: July 3, 2015
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Magnetic field induced transition in vanadium spinels.
E D Mun1, Gia-Wei Chern2, V Pardo3
1NHMFL Materials Physics and Applications, T-4 and CNLS, Los Alamos Laboratory (LANL), Los Alamos, New Mexico 87545, USA.
Physical Review Letters
|February 4, 2014
Summary
We observed a field-induced quantum phase transition in vanadium spinels (AV2O4). This transition in MgV2O4 and multiferroic CdV2O4 affects magnetic order and electric polarization, explained by crystal field effects.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Magnetism
Background:
- Vanadium spinels (AV2O4) exhibit complex magnetic behaviors.
- Strong spin-orbit coupling is characteristic of these materials.
- Understanding field-induced transitions is crucial for novel magnetic materials.
Purpose of the Study:
- To investigate the magnetic properties of CdV2O4 and MgV2O4 under high pulsed magnetic fields.
- To identify and characterize field-induced quantum phase transitions.
- To elucidate the role of crystal field effects in these transitions.
Main Methods:
- Experiments using pulsed magnetic fields up to 65 Tesla.
- Magnetization measurements on single-crystal samples.
- Theoretical modeling incorporating spin-orbit coupling and trigonal crystal fields.
Main Results:
- A distinct jump in magnetization observed in MgV2O4 at approximately 40 Tesla, signaling a quantum phase transition.
- Suppression of electric polarization in multiferroic CdV2O4 concurrent with the field-induced transition.
- Successful modeling of experimental results by including local trigonal crystal field effects.
Conclusions:
- The study reveals field-induced quantum phase transitions in vanadium spinels.
- Trigonal crystal field effects are key to understanding the observed magnetic and electric responses.
- These findings provide insights into the control of magnetic order and multiferroicity.
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